You can quickly remove the backgrounds from your images and give them the "green screen" look using GIMP, and weblog ThemBid.com (which published the companion tutorial for Photoshop last week) demonstrates the process. The Extract filter does the heavy lifting in Photoshop, but there is no equivalent to Extract in GIMP. GIMPers must use a more rudimentary technique of outlining the image and then adding an alpha layer as the new background. The results in Photoshop and GIMP look practicallyidentical.